# What could be done to reinvent the Affordaplane to a more homogeneous project?

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#### TLAR

##### Banned
When I first started learning about home built aircraft, it was so easy to criticize the design, and I still do. I keep my criticism to my self.
Lots of criticisms here on HBA.
Most of the guilty have never designed any aircraft!
Design an aircraft and show it off here on HBA. You will certainly be mad when you do!
Always someone smarter, always a better way. Lmao

#### challenger_II

##### Well-Known Member
You must have been a carpenter in a former life: you be good at hitting the nail on the head, first time.

There's an old saying: "If it is a stupid idea, and it works, then it ain't stupid!"

When I first started learning about home built aircraft, it was so easy to criticize the design, and I still do. I keep my criticism to my self.
Lots of criticisms here on HBA.
Most of the guilty have never designed any aircraft!
Design an aircraft and show it off here on HBA. You will certainly be mad when you do!
Always someone smarter, always a better way. Lmao

#### erkki67

##### Well-Known Member
Correct rivets are probably more expensive than the bolts by a factor of 100, and require tools that are way more expensive than a wrench. I am assuming direct one for one substitute.

A regular Cherry is $2 a rivet or more. A really special one might be$15 for one. You can get a lot of AN3 bolts for $15. You can get a lot lot more grade 5 bolts. Drilling the holes are going to be about the same effort, done correctly. Redesigned will take a lot of effort unless it’s a shotgun approach. Start taking the cheap out and it’s not cheap. No one says that you must use aircraft grade rivets for the price of a condo. there are many high resistance and vibration resistant rivets out there, that are perfect for such a construction- #### Fiberglassworker ##### Active Member For non certified aircraft. there is a commercial locking rivet by Cherry called the Cherry Q rivet. They vary in price from$0,25 to $0.67 each depending on size and quantity, they are similar in design to a pop rivet except the stem locks in. Originally designed for trailers in the trucking industry. #### pilotarix ##### Active Member Hi Thanks for your response. I got some more information about riveting the whole thing. There is one guy that used rivets on his A-Plane. Here is his video He used stainless steel rivets 3/16 which would not be my first choice. Definitely not. I am not an enginieer of any kind, but based on some common sense I would assume that the rivets used in such a project should safely retain their lock bolts to maintain their shear strength. This is the case with CherryMax and CherryLock rivets. They are also available for the material thickness. At least the CherryLock rivets seem to require a special tool to set them correctly. These tools are not cheap, they are indeed very expensive. However, they should have the strength to hold a project like this together. One problem for the unexperienced builder will be to figure out the correct amount and spacing of rivets on the gussets. One row or two rows and the like. Maybe to much to do ... #### challenger_II ##### Well-Known Member One can obtain stainless BSPQ rivets commercially, that have stainless stems, and the stub is retained in the rivet body. Many of the current ultralight aircraft kits use these rivets. You can easily find the shear, and tensile, load information of the rivets. On key item is to ensure you (a) have a long enough "grip" for the two metal thicknesses, and to (b) have adequate metal thicknesses to not tear, or deform, allowing the riveted joint to fail. #### blane.c ##### Well-Known Member HBA Supporter #### Fiberglassworker ##### Active Member Hi Thanks for your response. I got some more information about riveting the whole thing. There is one guy that used rivets on his A-Plane. Here is his video He used stainless steel rivets 3/16 which would not be my first choice. Definitely not. I am not an enginieer of any kind, but based on some common sense I would assume that the rivets used in such a project should safely retain their lock bolts to maintain their shear strength. This is the case with CherryMax and CherryLock rivets. They are also available for the material thickness. At least the CherryLock rivets seem to require a special tool to set them correctly. These tools are not cheap, they are indeed very expensive. However, they should have the strength to hold a project like this together. One problem for the unexperienced builder will be to figure out the correct amount and spacing of rivets on the gussets. One row or two rows and the like. Maybe to much to do ... Correct the Cherry lock rivets require a double action tool to set the locking collar. The Cherry max rivets on the other hand can be set with an ordinary Pop riveter in the smaller sizes, the bigger ones require an air operated or hydraulic riveter. #### GeeZee ##### Well-Known Member HBA Supporter Some of the better quality hand riveters advertise that they will pull Cherry Max rivets. I think ATS and of course Amazon sells them. #### pilotarix ##### Active Member Hi all, Thanks for the input. I went on and ordered some CherryMax rivets at aircraft spruce. I do have a pneumatic riveter, but that will unlikely pull these rivets, so I also ordered a hand riveter capable of doing CherryMax rivets. The rivets I ordered have the appropriate length for the intended job, which is fastening two sheets of 1/8 thick aluminum together. Hence their grip length needs to be 0.250". That is easy to figure out. What is more difficult to figure out is the correct diameter of the rivet. There seems to be a rule for solid rivets - the diameter of the rivet should be at least 3 times the thickness of the sheet that will be riveted. I could not find anything like that for pop rivets. Also, there is information for pitch spacing and edge distance published, but again for solid rivets in structural applications. Unfortunately, I cannot find any information in that regard for pop rivets. Is it safe to assume that that is the same with pop rivets? At least for the diameter, that would make a very big pop rivet in my case. The sheet thickness is 1/8, 3 x1/8 = 3/8 = 0.375" (9.52 mm), that's would be a big rivet to pull. Unlikely. Anyhow, if somebody knows where to read about or get more information about pop rivets in structural aviation applications, please let me know. BTW, the CherryMAX rivets, which I think, might be the correct ones to use, have a shear strength of about 1000 lbs. #### challenger_II ##### Well-Known Member One suggestion is to find the shear strength of your particular rivet. Determine how many rivets you will have per cluster. This, plus the shear strength of the material you are riveting, will put you in the ball park of how much shear stress your cluster will withstand. #### Dee ##### Member EF: Some folks you pay heed to, others you take what they say with a grain of salt. At the end of the day, One has to build/buy to suit their specific needs. For painless folding wings, the Kolb system is hard to beat: simple, easy, and a one-man job. That's funny, I currently have a Kolb firefly with a Rotax 447. Previously, I sold an ultraCub with a half VW engine. Now I'm looking to build something simple like an Affordaplane to put a more reliable half VW engine on it. However, I'm not able to find support for the Affordaplane. Where can I find support Affordaplane? Thanks for your help. #### erkki67 ##### Well-Known Member That's funny, I currently have a Kolb firefly with a Rotax 447. Previously, I sold an ultraCub with a half VW engine. Now I'm looking to build something simple like an Affordaplane to put a more reliable half VW engine on it. However, I'm not able to find support for the Affordaplane. Where can I find support Affordaplane? Thanks for your help. At Facebook, there is a huge community #### erkki67 ##### Well-Known Member Hi all, Thanks for the input. I went on and ordered some CherryMax rivets at aircraft spruce. I do have a pneumatic riveter, but that will unlikely pull these rivets, so I also ordered a hand riveter capable of doing CherryMax rivets. The rivets I ordered have the appropriate length for the intended job, which is fastening two sheets of 1/8 thick aluminum together. Hence their grip length needs to be 0.250". That is easy to figure out. What is more difficult to figure out is the correct diameter of the rivet. There seems to be a rule for solid rivets - the diameter of the rivet should be at least 3 times the thickness of the sheet that will be riveted. I could not find anything like that for pop rivets. Also, there is information for pitch spacing and edge distance published, but again for solid rivets in structural applications. Unfortunately, I cannot find any information in that regard for pop rivets. Is it safe to assume that that is the same with pop rivets? At least for the diameter, that would make a very big pop rivet in my case. The sheet thickness is 1/8, 3 x1/8 = 3/8 = 0.375" (9.52 mm), that's would be a big rivet to pull. Unlikely. Anyhow, if somebody knows where to read about or get more information about pop rivets in structural aviation applications, please let me know. BTW, the CherryMAX rivets, which I think, might be the correct ones to use, have a shear strength of about 1000 lbs. The thinnest material to be riveted times 3 equals the rivet diameter. I’ve found Hemlock Rivets of 1/4” in diameter! #### Bigshu ##### Well-Known Member Everybody has Choices in Life! You can Piss & Moan about Hanger rent while using a$600 Cell Phone, CABLE TV, going out to Eat, going to a Show, other Events, etc. You can choose to use these Over-Priced $4,500+ Engines or build your own for 1/4th the Cost. You can live in town and Pay Hanger Rent or buy a place in the Country and have your own Hanger and Airfield! That$125/month 1500/yr, can Buy a Distressed Property to just have your own Hanger an Airstrip.
That's the approach I've been working on lately, since hangar space is so limited. What do you find to be the best place to find the distressed properties? Is there a listing for Sherriff's sales and such? Not sure about my ability to fly out of a turf field, but a workshop/hangar would be nice.

#### karmarepair

##### Well-Known Member
HBA Supporter
The thinnest material to be riveted times 3 equals the rivet diameter. I’ve found Hemlock Rivets of 1/4” in diameter!
On the Affordaplane, that works out to a 3/8" diameter rivet. Good luck finding pulled rivets that size, and even more luck trying to pull them.

Once I started looking, I was a little surprised how light and cheap bolts are compared to rivets. AN-3-24 bolt for example is about $0.80 in quantity, add a washer and a nylock, call it$1.10. TWO 3/16 stainless commercial pull rivets are almost exactly the same cost in similar quantities, and any higher grade than that (Closed End, Q, Cherry-Max) will be MORE. The rivets will be lighter, but it hardlly seems enough to make much of a difference, and putting the pilot on a diet is probably more cost effective.

Others have described some of the failings of this design, but watching Jon build one, and doing a little digging, is making me go "hmmmm" instead of my previous scoffing.

#### erkki67

##### Well-Known Member
What do you do of you dont habe access for AN Bolts reasonably priced?!

#### ElectricFlyer

##### Well-Known Member
HBA Supporter
What do you do if you dont have access for AN Bolts reasonably priced?!
Well - if in a critical function I would say pray!

I have had to order some during my mods I am doing to my trike - rotated my engine and had to extend frame upwards to maintain same thrust point. So I put them where I think it is critical like keeping wing and engine frame attached to the main frame. What is kicking me is when I have had to order, usually just bad planning and or lack of foresight, shipping is the same cost - 11$in bolts and 11$ in shipping. I would drive to get them but 1.5 hrs away.

In the end I dont want to be staring up from Hell for lack of one poor bolt
Cheers

#### Aerowerx

##### Well-Known Member
What do you do of you dont habe access for AN Bolts reasonably priced?!
Take up knitting????

#### erkki67

##### Well-Known Member
Or riveting blindrivets used in aviation too!